JPS609301A - Slip preventing device of electric railcar - Google Patents

Abstract

PURPOSE:To obtain a slip preventing device which has good responsiveness by operating a DC series motor in a shunt characteristic at the slip occurring time. CONSTITUTION:When a slip occurs at wheels driven by a DC series motor having an armature A1 and a field F1, a slip signal is generated from a slip detector SL1, a switch S1 is opened, and a thyristor SCR1 is conducted. A maximum value priority circuit 5 reads out the current value of the motor for driving wheels which do not slip via current transformers CT1-CTn and selects the maximum one as a main circuit current. A chopper controller 8 controls a chopper 7 in response to the deviation between the main circuit current and the present current value detected by a current transformer CT0. At this time, since a current is flowed to the field F1 via a bypass circuit of the thyristor SCR1 without intermediary of the armature A1, the motor becomes to run in a shunt characteristic, and the wheels are readhered.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a slip prevention device for an electric vehicle, and more particularly to a control device for a driving n-flow series motor to facilitate readhesion when wheels slip.

[Background of the invention]

Electric cars driven by DC series-wound motors have a potentially valuable characteristic in that once the wheels start idling, the idling speed increases divergently, leading to large idling.

Tired of wheels! Known methods for re-sticking wheels when they roll include a method that detects wheel slip and lowers the motor voltage, and a method that applies mechanical brakes to wheels that are slipping. However, in the previous method, a generator is used like a diesel-electric locomotive! 1. In the case of an electric car called υhaya, the field current of the generator must be controlled to lower rli and lt, so the response is slow, and if idling occurs due to the regulation of the electric helix, the main circuit will be damaged. The voltage increases dramatically, and the current in the motor that is not rotating also increases, causing torque fluctuations, which has the disadvantage that wheels that have not been spinning before are induced to spin. . In addition, in the latter method, the brakes are activated using compressed air, etc.
The problem was that it took a long time to respond, and that the re-adhesion performance varied depending on the unstable element of friction between the wheel and the plate.

By the way, in order to re-stick a vehicle that has been spinning,
The torque of the electric motor must be reduced below a value corresponding to the permissible coefficient of adhesion between wheel and rail. therefore,
If the response of the re-adhesion device is slow, the idling speed of the wheel will increase and the permissible adhesion coefficient will become very small. Decrease the usage adhesive coefficient of the entire car,
Decrease the performance of electric cars.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide an entire slip prevention device for an electric vehicle with good responsiveness, without the above-mentioned drawbacks of the prior art.

[Summary of the invention]

In order to achieve this object, the present invention has the following object: When a skid occurs, % mud is poured onto the direct field winding of a direct current series motor that drives dependent wheels without passing through the armature. Direct current @
The feature is that the %@ machine is operated with shunt winding characteristics.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is an electrical circuit diagram of an idling prevention bag fi according to an embodiment of the present invention. In this figure, 1 and 2 are the armature and field of the alternating current generator, and 3 is a field control device that controls the field current according to the set speed.

4 is a rectifier that converts the output of the alternating current generator into direct current, A
1 to A, F, and to Fn are the armature and field of a DC series motor that is the main motive for the side movement of the electric vehicle, and these DC series motors have an output of the rectifier 4.
Each is connected in parallel.

The configuration of the main circuit for driving the electric vehicle described above is the same as the conventional one, but in this embodiment, the following slipping prevention device is added to the top.

That is, PQ, ~PGn are DC series-motor armature A
The speed generators SL, -SL, connected to I-An1 or the axle driven by it, compare the rotational speed detected by each speed generator PG, ~PGn with a preset reference speed. When the rotation speed exceeds the reference speed, the wheel slip detector determines that wheel slip has occurred and outputs a full wheel slip signal. (-R+-8CRn is a thyristor that becomes conductive when the wheel slip signal is applied to its gate , Sl, Sn are switches that are normally closed and are opened by the idling signal, CT, ~CTn are current transformers that detect the entire current value of the motor, and CTo is the current value of the main circuit. In other words, the current transformer 5 detects the sound of the current flowing through all DC series winding motors, and the current transformer 5 starts operation when a slip signal is generated from any one of the slip detectors SL1 to FSLn. A maximum value priority circuit inputs each output of CT1 to CTn through the switches S and ~Sn trays, selects and outputs the maximum value, 6 is a multiplier that multiplies the output of this maximum value priority circuit by kn, 7 8 is a chopper control device that inputs the output of the multiplier 6 and the output of the converter CTo, calculates the deviation, and controls the chopper 72 so that the deviation becomes equal to 5CkL, ~SC⇠n, capacity 0+L direct winding engine electric wire A1~Anq
A bypass circuit is formed.

Now, suppose that a wheel that is being driven by an IA series series motor consisting of armature A1 and field F is idling.
Since the rotational speed of armature A is higher than the rotational speed of other armatures, the speed generator 1p't connected to armature A
When the output of P G + exceeds the reference speed, rotation detector S
A look-over signal is generated from L. This idling signal is sent to the thyristors Set+, , switch S] and the maximum value priority circuit 5, so that the thyristors 5C1l, , h conduct and close the bypass circuit of the armature A, and the switch S
1 is in the open state as shown in the figure, the input circuit of the output of the flow device CT to the maximum value priority circuit 5 is cut off, and further, the operation of the maximum value priority circuit 5 is started. Maximum value priority circuit 5
Now, the variable vjL device CIll, ~(: l1ln) that detects the current value of the DC series-wound electric motor 4M (At+11.) ~ (An + Fn) that drives the wheels that are not idling.
input the outputs of , select the largest one of them, and output it. This output is multiplied by 0 in the multiplier 6, but considering this as the current value of the main circuit during normal times before the trivia occurs,
Chi Flow Control 11j Device 8 VC calculates the deviation from the current current value detected by the current transformer CTo, and adjusts it so that this deviation becomes zero, that is, so that the current value of the main circuit returns to normal. By controlling the chopper 7 and using the bypass circuit of the chopper 7 and the thyristor SCR, a current is applied to the field 1 without going through the armature A. Flow.

In a DC series motor, when the wheels idle, both the armature current and the field current decrease due to the armature's back electromotive force, and the idle speed increases according to the so-called series winding characteristic. However, in this embodiment, as described above, the reduced current is supplied to the field l·1 whose current has decreased due to the occurrence of idle rotation without passing through the commutated gold armature A, so that The DC series-wound motor (A, +1!″l) that drives the rolling wheel tube has shunt-winding characteristics. Therefore, when the idling speed increases, the armature current rapidly decreases due to the back electromotive force of armature A. Along with this, the output torque also decreases, and the wheel re-adhesively takes place in balance with the load torque.In addition, the response speed of this re-adhesive track is different from that of the conventional method, which does not include large inductance or mechanical elements in the circuit. Therefore, compared to the previous case of 1.5 seconds or more, the response speed of the armature current, that is, the response speed of the armature current, which is determined by the declarator circuit time constant of about 01 seconds, is extremely fast, and it is possible to realize adaptation a of readhesion. I can do it.

FIG. 2 is a characteristic diagram showing speed changes during idling.

In the case of the conventional 1LtJJJ machine, as shown by the curve Vs, at time 1. When slipping occurs at time t, the speed increases in a short period of time due to its series winding characteristic. However, in the case of the above embodiment, as shown by the curve Vc, when slipping occurs at time t, the speed increases rapidly due to its shunt winding characteristic. Since the output torque decreases at , the idling speed does not increase, and re-adhesion starts a short time later at time .

Further, FIG. 3 is a characteristic diagram showing changes in current of the electric motor during idling. In the case of a conventional electric motor, as shown by the curve Cs, when idling occurs at time t1, both the Kamehurako' east current and the field current decrease, but in the case of the above embodiment, , time 1. When the motor idles at t, the control device operates upon detecting the idle at time t, and the field 4rb current, which was decreasing, is maintained at the value before the motor starts spinning, as shown by the curve Ct.
The back electromotive force of the armature increases and the armature current rapidly decreases as shown by the curve Ca, and re-adhesion starts at time t3 when the armature current decreases to about half of the value before nitriding.

〔Effect of the invention〕

As explained above, according to the present invention, the torque generated by the electric motor is reduced in a short time by using the straight 6ir when rolling occurs, and the straight winding abrasive machine is operated with the shunt winding characteristic, leading to re-adhesion. be able to. In addition, since the slipping speed does not develop significantly, there is little decrease in the coefficient of viscosity between the wheel and the rail (Q), and the amount of decrease in motor torque required to re-adhesion is smaller than in the conventional case. Therefore, it is possible to increase the viscosity coefficient used for the electric vehicle as a whole. Furthermore, due to idle rotation, the current flowing through the power supply will not change, as it will flow through the field.

For this reason, it is possible to prevent the negative effect that the voltage in the circuit increases due to the strict regulation, causing the current in the motor (C) which is not causing the idling to become concentrated and causing the idling to occur.

Figure 1 shows 'A'-'l of an electric car according to an embodiment of the present invention.
iI < 1 degree electric circuit diagram showing the prevention device, Figure 2 is 'tortoise!' during idling! S! Characteristic diagram showing speed changes of II aircraft, nest 3
The figure is a characteristic diagram showing changes in current of the motor during idling.

1.2... Armature and lift of alternator, 4
...... Rectifier, 5... Maximum value priority circuit,
6... 10 degree vessel, 7... chi day brim,
8...Chopper control device, A, -An, F
', -Fn... Armature and field of DC series motor, CIll, , CIll, -CTn...
,, current transformer, P(jl~PCin...speed generation'
Turtle machine, SL, ~SL, ... Idle rotation detector, 5ct
t, ~SCI too n...Thyristor, S1~S
n... Switch.

#11 Diagram Figure 2 Figure 3

Claims (1)

[Claims] 1. In an electric vehicle equipped with a DC power source and a plurality of DC series motors each connected in parallel to the DC power source, a means for detecting wheel slippage, and a means for detecting wheel slippage. The DC series motor that drives the detected idling wheel is equipped with a means for applying electric current to the series field winding of the DC series motor that drives the detected idling wheel, without the armature winding. A slip prevention device for an electric vehicle, which is characterized by having a shunt-winding characteristic that allows the vehicle to operate in one direction. 2.% Allowance In claim 1, it is provided that a current value is applied to the series field winding of the direct-current series motor that drives the idling wheel t1, and a side excitation 1- is applied to the wheel that is not idling. Note f) ii. A slip prevention device for an electric car that requires the current value to be approximately equal to the current value of the direct motor.